[*]Latest official estimates suggest London will grow 8.8% in the decade to 2026[*]City will be home to 9.54m as birth rate and immigration push up numbers[*]Every region of England is due to see population rise over the period, ONS says[*]Nearly half the predicted increase - 1.72million - is accounted for by immigration [*]Separate ONS figures show Romanian second-most common non-UK nationality